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NARROW
GeoRef Subject
-
all geography including DSDP/ODP Sites and Legs
-
Africa
-
East Africa (1)
-
North Africa
-
Atlas Mountains
-
Moroccan Atlas Mountains
-
Anti-Atlas (2)
-
-
-
Morocco
-
Moroccan Atlas Mountains
-
Anti-Atlas (2)
-
-
-
-
West Africa
-
Mauritanides (1)
-
-
West African Craton (1)
-
-
Alexander Terrane (2)
-
Altiplano (1)
-
Anglesey (1)
-
Arctic region
-
Greenland
-
East Greenland (1)
-
-
Svalbard
-
Spitsbergen (1)
-
-
-
Arran (1)
-
Asia
-
Altai Mountains
-
Mongolian Altai (1)
-
-
Arabian Peninsula (1)
-
Far East
-
China
-
Jiangxi China (1)
-
Xinjiang China
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Junggar (1)
-
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Yangtze Platform (1)
-
Yunnan China
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Jinning China (1)
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Mongolia
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Mongolian Altai (1)
-
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Gobi Desert (1)
-
Middle East
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Iran (1)
-
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Siberian Platform (1)
-
-
Atlantic Ocean
-
North Atlantic
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Bay of Fundy (1)
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Celtic Sea (1)
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Flemish Cap (1)
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Georges Bank (2)
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Gulf of Saint Lawrence (1)
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Irish Sea (3)
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Jeanne d'Arc Basin (1)
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Northwest Atlantic (2)
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-
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Atlantic region (1)
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Australasia
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New Zealand
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Bay of Plenty (1)
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Taupo (1)
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Avalon Zone (12)
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Bell Island (3)
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Caledonides (18)
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Canada
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Eastern Canada
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Baffin Island (1)
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Gander Zone (14)
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Maritime Provinces
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New Brunswick
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Charlotte County New Brunswick (1)
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Gloucester County New Brunswick
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Bathurst mining district (1)
-
-
Restigouche County New Brunswick (3)
-
Saint John County New Brunswick
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Saint John New Brunswick (2)
-
-
-
Nova Scotia
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Antigonish County Nova Scotia (2)
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Cape Breton Island
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Cape Breton County Nova Scotia (1)
-
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Cobequid Highlands (3)
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Yarmouth County Nova Scotia (1)
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Prince Edward Island (2)
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Meguma Terrane (15)
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Newfoundland and Labrador
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Labrador (1)
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Newfoundland
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Avalon Peninsula (5)
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Baie Verte Peninsula (2)
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Burin Peninsula (1)
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Notre Dame Bay (3)
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Saint John's Newfoundland and Labrador (1)
-
-
-
Ontario
-
Hamilton Ontario (1)
-
-
Quebec
-
Anticosti Island (1)
-
Beauce County Quebec (1)
-
Gaspe Peninsula (2)
-
Sherbrooke County Quebec (1)
-
Thetford Mines (1)
-
-
-
Elzevir Terrane (1)
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Nunavut
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Baffin Island (1)
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Ellesmere Island (2)
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Queen Elizabeth Islands
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Ellesmere Island (2)
-
-
Western Canada
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Alberta (1)
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British Columbia (1)
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Yukon Territory (1)
-
-
-
Chaleur Bay (1)
-
Commonwealth of Independent States
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Russian Federation
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Siberian Platform (1)
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-
-
Dunnage Zone (7)
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Eagle Lake (1)
-
Europe
-
Baltic region
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Estonia (1)
-
-
Central Europe
-
Bohemian Massif (3)
-
Sudeten Mountains
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Izera Mountains (1)
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Karkonosze Mountains (1)
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Southern Europe
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Iberian Peninsula
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Iberian Massif (2)
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Ossa-Morena Zone (1)
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Portugal (3)
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Spain
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Galicia Spain
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Lugo Spain (1)
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Stavelot-Venn Massif (1)
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Variscides (5)
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Western Europe
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Belgium (1)
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France
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Armorican Massif (1)
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Var France
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Maures Massif (1)
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Ireland
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Donegal Ireland
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Ardara Pluton (2)
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Galway Ireland
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Connemara (1)
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Kerry Ireland
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Dingle Peninsula (1)
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Leinster (2)
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Limerick Ireland (1)
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Mayo Ireland (2)
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Wexford Ireland (1)
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Wicklow Ireland (1)
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Scandinavia
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Koli Nappe (1)
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Norway
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Finnmark Norway (1)
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Gudbrandsdalen (1)
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Nordland Norway (1)
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Southern Norway (1)
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Sweden
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Vastergotland (1)
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United Kingdom
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Great Britain
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England
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Cumbria England (1)
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East Midlands (1)
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Ingleton England (1)
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Pennines (2)
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Shropshire England (2)
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Warwickshire England (1)
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Welsh Borderland (1)
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Yorkshire England
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North Yorkshire England (1)
-
-
-
Scotland
-
Argyllshire Scotland
-
Kintyre (1)
-
-
Firth of Clyde (1)
-
Great Glen Fault (2)
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Moine thrust zone (2)
-
Scottish Highlands
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Grampian Highlands (2)
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Scottish Northern Highlands (1)
-
-
-
Wales
-
Anglesey Wales (1)
-
Gwynedd Wales
-
Harlech Dome (1)
-
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Welsh Basin (2)
-
-
-
Isle of Man (1)
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-
-
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Grand Banks (1)
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Green Mountains (1)
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Highland Boundary Fault (3)
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Hikurangi Margin (1)
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Hudson Bay Basin (1)
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Lake District (2)
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Malvern Hills (1)
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Marathon Basin (1)
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Maritimes Basin (1)
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Meseta (1)
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Mexico
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Coahuila Mexico (1)
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Guerrero Mexico (1)
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Guerrero Terrane (1)
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Midland Valley (2)
-
North America
-
Appalachian Basin (2)
-
Appalachians
-
Blue Ridge Mountains (1)
-
Blue Ridge Province (2)
-
Central Appalachians (4)
-
Northern Appalachians (33)
-
Piedmont (7)
-
Southern Appalachians (8)
-
-
Basin and Range Province (1)
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Canadian Shield
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Churchill Province
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Rae Province (1)
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Grenville Province (1)
-
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Humber Zone (3)
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Michigan Basin (1)
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North American Cordillera (2)
-
Pedregosa Basin (2)
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Rocky Mountains (1)
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Saint Elias Mountains (1)
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Transcontinental Arch (1)
-
-
North Island (1)
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Northern Highlands (1)
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Orcadian Basin (1)
-
Pacific Ocean
-
North Pacific
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Northwest Pacific
-
Celebes Sea (1)
-
-
-
West Pacific
-
Indonesian Seas
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Celebes Sea (1)
-
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Northwest Pacific
-
Celebes Sea (1)
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-
-
Pacific region (1)
-
Prince of Wales Island (1)
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Russian Platform (1)
-
South America
-
Amazonian Craton (4)
-
Andes
-
Eastern Cordillera (1)
-
-
Peru (2)
-
-
South Mountain Batholith (1)
-
Southern Uplands (4)
-
United States
-
Alabama
-
Tallapoosa County Alabama (1)
-
-
Alaska
-
Alexander Archipelago (1)
-
-
Anadarko Basin (3)
-
Arizona
-
Mogollon Rim (1)
-
-
Arkansas
-
Clark County Arkansas (1)
-
Pike County Arkansas (1)
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Pulaski County Arkansas (1)
-
-
Arkoma Basin (2)
-
Blue Ridge Mountains (1)
-
Bronson Hill Anticlinorium (2)
-
California (1)
-
Carolina Terrane (5)
-
Colorado (1)
-
Colorado Plateau (1)
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Connecticut
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New London County Connecticut (1)
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Windham County Connecticut (1)
-
-
Connecticut Valley (1)
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Delaware
-
New Castle County Delaware (1)
-
-
Delaware Basin (1)
-
Denver Basin (1)
-
Eastern U.S. (4)
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Forest City Basin (2)
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Georgia (3)
-
Great Smoky Mountains (1)
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Illinois Basin (2)
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Maine
-
Chain Lakes Massif (2)
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Franklin County Maine (2)
-
Hancock County Maine (1)
-
Lincoln County Maine (1)
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Oxford County Maine (2)
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Penobscot Bay (2)
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Sagadahoc County Maine (1)
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Waldo County Maine (1)
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Washington County Maine (1)
-
-
Maryland
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Baltimore County Maryland
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Baltimore Maryland (1)
-
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Howard County Maryland (1)
-
-
Massachusetts
-
Berkshire County Massachusetts
-
Berkshire Hills (1)
-
-
Essex County Massachusetts (2)
-
Middlesex County Massachusetts (1)
-
Suffolk County Massachusetts
-
Boston Massachusetts (1)
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-
Worcester County Massachusetts (1)
-
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Midcontinent (4)
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Montana (2)
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Narragansett Basin (1)
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New England (14)
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New Hampshire (4)
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New Jersey (1)
-
New York
-
New York City New York
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Manhattan (1)
-
-
-
Newark Basin (1)
-
North Carolina
-
Davidson County North Carolina (2)
-
Stanly County North Carolina (1)
-
-
Oklahoma
-
Arbuckle Mountains (1)
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Arbuckle Uplift (1)
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Wichita Mountains (1)
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Wichita Uplift (1)
-
-
Paradox Basin (1)
-
Pennsylvania
-
Delaware County Pennsylvania (1)
-
-
Pine Mountain Window (2)
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Rhode Island (6)
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South Carolina (2)
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Tennessee (1)
-
Texas
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Fort Worth Basin (3)
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Marathon Geosyncline (1)
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-
Utah (1)
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Vermont (4)
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Virginia (2)
-
Wyoming (1)
-
-
-
commodities
-
barite deposits (1)
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brines (1)
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fluorspar deposits (1)
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metal ores
-
base metals (2)
-
copper ores (10)
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gold ores (11)
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lead ores (6)
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lead-zinc deposits (3)
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lithium ores (1)
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molybdenum ores (3)
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silver ores (5)
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tin ores (1)
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tungsten ores (3)
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zinc ores (8)
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mineral deposits, genesis (10)
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mineral exploration (5)
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oil and gas fields (1)
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petroleum (5)
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placers (1)
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-
elements, isotopes
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carbon
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C-13/C-12 (4)
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chemical ratios (2)
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halogens
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fluorine (1)
-
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hydrogen
-
D/H (1)
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deuterium (1)
-
-
isotope ratios (38)
-
isotopes
-
radioactive isotopes
-
Pb-206/Pb-204 (2)
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Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (2)
-
Sm-147/Nd-144 (10)
-
-
stable isotopes
-
C-13/C-12 (4)
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D/H (1)
-
deuterium (1)
-
Hf-177/Hf-176 (11)
-
Nd-144/Nd-143 (16)
-
O-18 (1)
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O-18/O-16 (9)
-
Pb-206/Pb-204 (2)
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Pb-207/Pb-204 (1)
-
Pb-207/Pb-206 (1)
-
Pb-208/Pb-204 (2)
-
S-34/S-32 (4)
-
Sm-147/Nd-144 (10)
-
Sr-87/Sr-86 (5)
-
-
-
large-ion lithophile elements (1)
-
Lu/Hf (8)
-
metals
-
actinides
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thorium (1)
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uranium (1)
-
-
alkali metals
-
cesium (2)
-
lithium (2)
-
-
alkaline earth metals
-
strontium
-
Sr-87/Sr-86 (5)
-
-
-
hafnium
-
Hf-177/Hf-176 (11)
-
-
lead
-
Pb-206/Pb-204 (2)
-
Pb-207/Pb-204 (1)
-
Pb-207/Pb-206 (1)
-
Pb-208/Pb-204 (2)
-
-
niobium (1)
-
precious metals (1)
-
rare earths
-
europium (1)
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lanthanum (1)
-
lutetium (4)
-
neodymium
-
Nd-144/Nd-143 (16)
-
Sm-147/Nd-144 (10)
-
-
samarium
-
Sm-147/Nd-144 (10)
-
-
ytterbium (1)
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yttrium (2)
-
-
tantalum (2)
-
tin (1)
-
titanium (2)
-
tungsten (1)
-
-
oxygen
-
O-18 (1)
-
O-18/O-16 (9)
-
-
sulfur
-
S-34/S-32 (4)
-
-
-
fossils
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burrows (2)
-
Graptolithina (3)
-
ichnofossils
-
Planolites (1)
-
-
Invertebrata
-
Arthropoda
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Mandibulata
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Crustacea
-
Ostracoda (1)
-
-
-
Trilobitomorpha
-
Trilobita
-
Ptychopariida
-
Olenidae (1)
-
-
-
-
-
Brachiopoda
-
Articulata
-
Strophomenida (1)
-
-
-
-
Metazoa (1)
-
microfossils
-
Conodonta (1)
-
-
palynomorphs
-
acritarchs (7)
-
-
Plantae (2)
-
problematic fossils (1)
-
-
geochronology methods
-
Ar/Ar (17)
-
fission-track dating (2)
-
K/Ar (1)
-
Lu/Hf (8)
-
paleomagnetism (15)
-
Pb/Pb (1)
-
Rb/Sr (3)
-
Sm/Nd (5)
-
thermochronology (1)
-
U/Pb (126)
-
U/Th/Pb (4)
-
-
geologic age
-
Cenozoic
-
Tertiary
-
Neogene
-
Pliocene
-
Cimmerian (1)
-
-
-
-
-
Dalradian (2)
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Berriasian (1)
-
-
Middle Cretaceous (1)
-
-
Jurassic
-
Middle Jurassic (1)
-
Upper Jurassic
-
Jeanne d'Arc Formation (1)
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Tithonian (1)
-
-
-
Newark Supergroup (1)
-
Triassic
-
Upper Triassic
-
Carnian (1)
-
-
-
upper Mesozoic (1)
-
-
Paleozoic
-
Acatlan Complex (2)
-
Bucksport Formation (1)
-
Cambrian
-
Acadian (2)
-
Lower Cambrian
-
Terreneuvian (4)
-
-
Middle Cambrian (6)
-
Upper Cambrian
-
Furongian (1)
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Goldenville Formation (2)
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-
-
Cape Elizabeth Formation (1)
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Carboniferous
-
Jackfork Group (1)
-
Johns Valley Formation (1)
-
Lower Carboniferous (4)
-
Mississippian
-
Lower Mississippian
-
Pocono Formation (1)
-
Tournaisian (1)
-
-
Middle Mississippian
-
Visean (1)
-
-
Upper Mississippian
-
Serpukhovian (1)
-
-
-
Namurian (1)
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Pennsylvanian
-
Lower Pennsylvanian
-
Bashkirian (1)
-
Haymond Formation (1)
-
Morrowan (2)
-
-
Middle Pennsylvanian
-
Atokan (1)
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Desmoinesian (1)
-
Moscovian (1)
-
-
Upper Pennsylvanian (1)
-
-
Upper Carboniferous
-
Westphalian (1)
-
-
-
Casco Bay Group (1)
-
Catskill Formation (1)
-
Devonian
-
Fisset Brook Formation (1)
-
Lower Devonian
-
Emsian (3)
-
Pragian (1)
-
-
Middle Devonian
-
Eifelian (1)
-
-
Old Red Sandstone (3)
-
Upper Devonian
-
Famennian (1)
-
-
-
Hartland Formation (1)
-
Leinster Granite (2)
-
lower Paleozoic
-
Berwick Formation (1)
-
Cape Phillips Formation (1)
-
Wilmington Complex (1)
-
-
Matapedia Group (1)
-
Merrimack Group (1)
-
middle Paleozoic (1)
-
Ordovician
-
Betts Cove Ophiolite (1)
-
Buchans Group (1)
-
Lower Ordovician
-
Arenigian (4)
-
Manx Group (1)
-
Tremadocian
-
Halifax Formation (1)
-
-
-
Martinsburg Formation (1)
-
Meguma Group (1)
-
Middle Ordovician
-
Ammonoosuc Volcanics (1)
-
Darriwilian (4)
-
Llanvirnian (1)
-
Table Head Group (1)
-
-
Miramichi Group (2)
-
Tetagouche Group (4)
-
Upper Ordovician
-
Caradocian (2)
-
Katian (3)
-
Sandbian (3)
-
-
Utica Shale (2)
-
Wild Bight Group (1)
-
-
Permian
-
Lower Permian (1)
-
-
Petersburg Granite (1)
-
Silurian
-
Lower Silurian
-
Grimsby Sandstone (1)
-
Llandovery (2)
-
Wenlock (2)
-
-
Middle Silurian (1)
-
Upper Silurian
-
Ludlow (2)
-
Pridoli (3)
-
-
-
upper Paleozoic (4)
-
Wissahickon Formation (2)
-
-
Phanerozoic (4)
-
Precambrian
-
Archean
-
Neoarchean (1)
-
-
Baltimore Gneiss (1)
-
upper Precambrian
-
Proterozoic
-
Coldbrook Group (2)
-
Dedham Granodiorite (2)
-
Mesoproterozoic
-
Belt Supergroup (1)
-
Fordham Gneiss (1)
-
-
Neoproterozoic
-
Cryogenian (2)
-
Ediacaran (23)
-
Hadrynian
-
Fourchu Group (1)
-
-
Maranon Complex (1)
-
Moine Supergroup (1)
-
Tonian (6)
-
Vendian (4)
-
-
Paleoproterozoic (8)
-
-
-
-
-
igneous rocks
-
igneous rocks
-
hypabyssal rocks (1)
-
plutonic rocks
-
anorthosite (1)
-
appinite (1)
-
diabase (1)
-
diorites
-
quartz diorites (1)
-
tonalite (5)
-
trondhjemite (1)
-
-
gabbros
-
norite (1)
-
-
granites
-
granite porphyry (1)
-
I-type granites (1)
-
monzogranite (1)
-
rapakivi (1)
-
S-type granites (2)
-
-
granodiorites (4)
-
lamprophyres (1)
-
pegmatite (4)
-
syenodiorite (1)
-
ultramafics (3)
-
-
porphyry (2)
-
volcanic rocks
-
adakites (1)
-
andesites
-
boninite (1)
-
-
basalts
-
mid-ocean ridge basalts (3)
-
ocean-island basalts (1)
-
tholeiite (2)
-
-
dacites (2)
-
pyroclastics
-
ignimbrite (2)
-
tuff (7)
-
-
rhyolites (12)
-
trachyandesites (3)
-
-
-
ophiolite (6)
-
-
metamorphic rocks
-
metamorphic rocks
-
amphibolites (3)
-
eclogite (3)
-
gneisses
-
augen gneiss (1)
-
granite gneiss (1)
-
orthogneiss (1)
-
paragneiss (1)
-
tonalite gneiss (1)
-
-
marbles (1)
-
metaigneous rocks
-
metabasalt (1)
-
metabasite (2)
-
metagabbro (3)
-
metagranite (1)
-
metarhyolite (1)
-
-
metaplutonic rocks (1)
-
metasedimentary rocks
-
metapelite (3)
-
metasandstone (1)
-
metasiltstone (1)
-
paragneiss (1)
-
-
metasomatic rocks
-
greisen (1)
-
-
metavolcanic rocks (7)
-
migmatites (2)
-
mylonites (4)
-
phyllites (2)
-
phyllonites (1)
-
quartzites (6)
-
schists
-
blueschist (4)
-
greenschist (1)
-
-
-
ophiolite (6)
-
turbidite (8)
-
-
minerals
-
arsenides
-
arsenopyrite (1)
-
-
carbonates
-
calcite (1)
-
dolomite (2)
-
-
halides
-
fluorides
-
topaz (1)
-
-
-
oxides
-
baddeleyite (1)
-
cassiterite (3)
-
rutile (1)
-
spinel (1)
-
uraninite (1)
-
-
phosphates
-
apatite (6)
-
monazite (12)
-
-
silicates
-
chain silicates
-
amphibole group
-
clinoamphibole
-
grunerite (1)
-
hornblende (2)
-
-
-
pyroxene group
-
clinopyroxene
-
spodumene (1)
-
-
-
-
framework silicates
-
feldspar group
-
alkali feldspar
-
K-feldspar (1)
-
-
plagioclase
-
albite (2)
-
-
-
silica minerals
-
coesite (1)
-
quartz (1)
-
-
-
orthosilicates
-
nesosilicates
-
garnet group (6)
-
titanite group
-
titanite (5)
-
-
topaz (1)
-
zircon group
-
zircon (113)
-
-
-
-
sheet silicates
-
chlorite group
-
chlorite (1)
-
-
illite (2)
-
mica group
-
biotite (4)
-
muscovite (9)
-
-
-
-
sulfates
-
barite (1)
-
-
sulfides
-
arsenopyrite (1)
-
sphalerite (1)
-
-
-
Primary terms
-
absolute age (133)
-
Africa
-
East Africa (1)
-
North Africa
-
Atlas Mountains
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Moroccan Atlas Mountains
-
Anti-Atlas (2)
-
-
-
Morocco
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Moroccan Atlas Mountains
-
Anti-Atlas (2)
-
-
-
-
West Africa
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Mauritanides (1)
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-
West African Craton (1)
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-
Arctic region
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Greenland
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East Greenland (1)
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Svalbard
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Spitsbergen (1)
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-
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Asia
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Altai Mountains
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Mongolian Altai (1)
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Arabian Peninsula (1)
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Far East
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China
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Jiangxi China (1)
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Xinjiang China
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Junggar (1)
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Yangtze Platform (1)
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Yunnan China
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-
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Mongolia
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Mongolian Altai (1)
-
-
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Gobi Desert (1)
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Middle East
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Iran (1)
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Siberian Platform (1)
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Atlantic Ocean
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North Atlantic
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Northwest Atlantic (2)
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-
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Atlantic region (1)
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Australasia
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New Zealand
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barite deposits (1)
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biogeography (3)
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brines (1)
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Canada
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Baffin Island (1)
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Gander Zone (14)
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Maritime Provinces
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New Brunswick
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Gloucester County New Brunswick
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Bathurst mining district (1)
-
-
Restigouche County New Brunswick (3)
-
Saint John County New Brunswick
-
Saint John New Brunswick (2)
-
-
-
Nova Scotia
-
Antigonish County Nova Scotia (2)
-
Cape Breton Island
-
Cape Breton County Nova Scotia (1)
-
-
Cobequid Highlands (3)
-
Yarmouth County Nova Scotia (1)
-
-
Prince Edward Island (2)
-
-
Meguma Terrane (15)
-
Newfoundland and Labrador
-
Labrador (1)
-
Newfoundland
-
Avalon Peninsula (5)
-
Baie Verte Peninsula (2)
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Burin Peninsula (1)
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Notre Dame Bay (3)
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Saint John's Newfoundland and Labrador (1)
-
-
-
Ontario
-
Hamilton Ontario (1)
-
-
Quebec
-
Anticosti Island (1)
-
Beauce County Quebec (1)
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Gaspe Peninsula (2)
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Sherbrooke County Quebec (1)
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Thetford Mines (1)
-
-
-
Elzevir Terrane (1)
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Nunavut
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Baffin Island (1)
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Ellesmere Island (2)
-
-
Queen Elizabeth Islands
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Ellesmere Island (2)
-
-
Western Canada
-
Alberta (1)
-
British Columbia (1)
-
Yukon Territory (1)
-
-
-
carbon
-
C-13/C-12 (4)
-
-
Cenozoic
-
Tertiary
-
Neogene
-
Pliocene
-
Cimmerian (1)
-
-
-
-
-
continental drift (9)
-
continental shelf (1)
-
crust (29)
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crystal chemistry (2)
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deformation (24)
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diagenesis (4)
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education (1)
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epeirogeny (1)
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Europe
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Baltic region
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Estonia (1)
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-
Central Europe
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Bohemian Massif (3)
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Sudeten Mountains
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Izera Mountains (1)
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Karkonosze Mountains (1)
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-
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Southern Europe
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Iberian Peninsula
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Iberian Massif (2)
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Ossa-Morena Zone (1)
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Portugal (3)
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Spain
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Galicia Spain
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Lugo Spain (1)
-
-
-
-
-
Stavelot-Venn Massif (1)
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Variscides (5)
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Western Europe
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Belgium (1)
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France
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Armorican Massif (1)
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Var France
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Maures Massif (1)
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-
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Ireland
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Donegal Ireland
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Ardara Pluton (2)
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Galway Ireland
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Connemara (1)
-
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Kerry Ireland
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Dingle Peninsula (1)
-
-
Leinster (2)
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Scandinavia
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Koli Nappe (1)
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Norway
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Sweden
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United Kingdom
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Yorkshire England
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North Yorkshire England (1)
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-
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Scotland
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Argyllshire Scotland
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Kintyre (1)
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Firth of Clyde (1)
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Great Glen Fault (2)
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Moine thrust zone (2)
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Scottish Highlands
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Scottish Northern Highlands (1)
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-
-
Wales
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Anglesey Wales (1)
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Gwynedd Wales
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Harlech Dome (1)
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Welsh Basin (2)
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-
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Isle of Man (1)
-
-
-
-
faults (40)
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fluorspar deposits (1)
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folds (11)
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foliation (7)
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geochemistry (30)
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geochronology (4)
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geophysical methods (9)
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glacial geology (1)
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Graptolithina (3)
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heat flow (3)
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hydrogen
-
D/H (1)
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deuterium (1)
-
-
ichnofossils
-
Planolites (1)
-
-
igneous rocks
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hypabyssal rocks (1)
-
plutonic rocks
-
anorthosite (1)
-
appinite (1)
-
diabase (1)
-
diorites
-
quartz diorites (1)
-
tonalite (5)
-
trondhjemite (1)
-
-
gabbros
-
norite (1)
-
-
granites
-
granite porphyry (1)
-
I-type granites (1)
-
monzogranite (1)
-
rapakivi (1)
-
S-type granites (2)
-
-
granodiorites (4)
-
lamprophyres (1)
-
pegmatite (4)
-
syenodiorite (1)
-
ultramafics (3)
-
-
porphyry (2)
-
volcanic rocks
-
adakites (1)
-
andesites
-
boninite (1)
-
-
basalts
-
mid-ocean ridge basalts (3)
-
ocean-island basalts (1)
-
tholeiite (2)
-
-
dacites (2)
-
pyroclastics
-
ignimbrite (2)
-
tuff (7)
-
-
rhyolites (12)
-
trachyandesites (3)
-
-
-
inclusions
-
fluid inclusions (3)
-
-
intrusions (47)
-
Invertebrata
-
Arthropoda
-
Mandibulata
-
Crustacea
-
Ostracoda (1)
-
-
-
Trilobitomorpha
-
Trilobita
-
Ptychopariida
-
Olenidae (1)
-
-
-
-
-
Brachiopoda
-
Articulata
-
Strophomenida (1)
-
-
-
-
isotopes
-
radioactive isotopes
-
Pb-206/Pb-204 (2)
-
Pb-207/Pb-204 (1)
-
Pb-208/Pb-204 (2)
-
Sm-147/Nd-144 (10)
-
-
stable isotopes
-
C-13/C-12 (4)
-
D/H (1)
-
deuterium (1)
-
Hf-177/Hf-176 (11)
-
Nd-144/Nd-143 (16)
-
O-18 (1)
-
O-18/O-16 (9)
-
Pb-206/Pb-204 (2)
-
Pb-207/Pb-204 (1)
-
Pb-207/Pb-206 (1)
-
Pb-208/Pb-204 (2)
-
S-34/S-32 (4)
-
Sm-147/Nd-144 (10)
-
Sr-87/Sr-86 (5)
-
-
-
lava (1)
-
magmas (15)
-
mantle (12)
-
Mesozoic
-
Cretaceous
-
Lower Cretaceous
-
Berriasian (1)
-
-
Middle Cretaceous (1)
-
-
Jurassic
-
Middle Jurassic (1)
-
Upper Jurassic
-
Jeanne d'Arc Formation (1)
-
Tithonian (1)
-
-
-
Newark Supergroup (1)
-
Triassic
-
Upper Triassic
-
Carnian (1)
-
-
-
upper Mesozoic (1)
-
-
metal ores
-
base metals (2)
-
copper ores (10)
-
gold ores (11)
-
lead ores (6)
-
lead-zinc deposits (3)
-
lithium ores (1)
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molybdenum ores (3)
-
silver ores (5)
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tin ores (1)
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tungsten ores (3)
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zinc ores (8)
-
-
metals
-
actinides
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thorium (1)
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uranium (1)
-
-
alkali metals
-
cesium (2)
-
lithium (2)
-
-
alkaline earth metals
-
strontium
-
Sr-87/Sr-86 (5)
-
-
-
hafnium
-
Hf-177/Hf-176 (11)
-
-
lead
-
Pb-206/Pb-204 (2)
-
Pb-207/Pb-204 (1)
-
Pb-207/Pb-206 (1)
-
Pb-208/Pb-204 (2)
-
-
niobium (1)
-
precious metals (1)
-
rare earths
-
europium (1)
-
lanthanum (1)
-
lutetium (4)
-
neodymium
-
Nd-144/Nd-143 (16)
-
Sm-147/Nd-144 (10)
-
-
samarium
-
Sm-147/Nd-144 (10)
-
-
ytterbium (1)
-
yttrium (2)
-
-
tantalum (2)
-
tin (1)
-
titanium (2)
-
tungsten (1)
-
-
metamorphic rocks
-
amphibolites (3)
-
eclogite (3)
-
gneisses
-
augen gneiss (1)
-
granite gneiss (1)
-
orthogneiss (1)
-
paragneiss (1)
-
tonalite gneiss (1)
-
-
marbles (1)
-
metaigneous rocks
-
metabasalt (1)
-
metabasite (2)
-
metagabbro (3)
-
metagranite (1)
-
metarhyolite (1)
-
-
metaplutonic rocks (1)
-
metasedimentary rocks
-
metapelite (3)
-
metasandstone (1)
-
metasiltstone (1)
-
paragneiss (1)
-
-
metasomatic rocks
-
greisen (1)
-
-
metavolcanic rocks (7)
-
migmatites (2)
-
mylonites (4)
-
phyllites (2)
-
phyllonites (1)
-
quartzites (6)
-
schists
-
blueschist (4)
-
greenschist (1)
-
-
-
metamorphism (40)
-
metasomatism (12)
-
Mexico
-
Coahuila Mexico (1)
-
Guerrero Mexico (1)
-
Guerrero Terrane (1)
-
-
mineral deposits, genesis (10)
-
mineral exploration (5)
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mining geology (1)
-
Mohorovicic discontinuity (2)
-
North America
-
Appalachian Basin (2)
-
Appalachians
-
Blue Ridge Mountains (1)
-
Blue Ridge Province (2)
-
Central Appalachians (4)
-
Northern Appalachians (33)
-
Piedmont (7)
-
Southern Appalachians (8)
-
-
Basin and Range Province (1)
-
Canadian Shield
-
Churchill Province
-
Rae Province (1)
-
-
Grenville Province (1)
-
-
Humber Zone (3)
-
Michigan Basin (1)
-
North American Cordillera (2)
-
Pedregosa Basin (2)
-
Rocky Mountains (1)
-
Saint Elias Mountains (1)
-
Transcontinental Arch (1)
-
-
ocean basins (3)
-
ocean floors (1)
-
oil and gas fields (1)
-
orogeny (40)
-
oxygen
-
O-18 (1)
-
O-18/O-16 (9)
-
-
Pacific Ocean
-
North Pacific
-
Northwest Pacific
-
Celebes Sea (1)
-
-
-
West Pacific
-
Indonesian Seas
-
Celebes Sea (1)
-
-
Northwest Pacific
-
Celebes Sea (1)
-
-
-
-
Pacific region (1)
-
paleoclimatology (5)
-
paleoecology (1)
-
paleogeography (57)
-
paleomagnetism (15)
-
Paleozoic
-
Acatlan Complex (2)
-
Bucksport Formation (1)
-
Cambrian
-
Acadian (2)
-
Lower Cambrian
-
Terreneuvian (4)
-
-
Middle Cambrian (6)
-
Upper Cambrian
-
Furongian (1)
-
Goldenville Formation (2)
-
-
-
Cape Elizabeth Formation (1)
-
Carboniferous
-
Jackfork Group (1)
-
Johns Valley Formation (1)
-
Lower Carboniferous (4)
-
Mississippian
-
Lower Mississippian
-
Pocono Formation (1)
-
Tournaisian (1)
-
-
Middle Mississippian
-
Visean (1)
-
-
Upper Mississippian
-
Serpukhovian (1)
-
-
-
Namurian (1)
-
Pennsylvanian
-
Lower Pennsylvanian
-
Bashkirian (1)
-
Haymond Formation (1)
-
Morrowan (2)
-
-
Middle Pennsylvanian
-
Atokan (1)
-
Desmoinesian (1)
-
Moscovian (1)
-
-
Upper Pennsylvanian (1)
-
-
Upper Carboniferous
-
Westphalian (1)
-
-
-
Casco Bay Group (1)
-
Catskill Formation (1)
-
Devonian
-
Fisset Brook Formation (1)
-
Lower Devonian
-
Emsian (3)
-
Pragian (1)
-
-
Middle Devonian
-
Eifelian (1)
-
-
Old Red Sandstone (3)
-
Upper Devonian
-
Famennian (1)
-
-
-
Hartland Formation (1)
-
Leinster Granite (2)
-
lower Paleozoic
-
Berwick Formation (1)
-
Cape Phillips Formation (1)
-
Wilmington Complex (1)
-
-
Matapedia Group (1)
-
Merrimack Group (1)
-
middle Paleozoic (1)
-
Ordovician
-
Betts Cove Ophiolite (1)
-
Buchans Group (1)
-
Lower Ordovician
-
Arenigian (4)
-
Manx Group (1)
-
Tremadocian
-
Halifax Formation (1)
-
-
-
Martinsburg Formation (1)
-
Meguma Group (1)
-
Middle Ordovician
-
Ammonoosuc Volcanics (1)
-
Darriwilian (4)
-
Llanvirnian (1)
-
Table Head Group (1)
-
-
Miramichi Group (2)
-
Tetagouche Group (4)
-
Upper Ordovician
-
Caradocian (2)
-
Katian (3)
-
Sandbian (3)
-
-
Utica Shale (2)
-
Wild Bight Group (1)
-
-
Permian
-
Lower Permian (1)
-
-
Petersburg Granite (1)
-
Silurian
-
Lower Silurian
-
Grimsby Sandstone (1)
-
Llandovery (2)
-
Wenlock (2)
-
-
Middle Silurian (1)
-
Upper Silurian
-
Ludlow (2)
-
Pridoli (3)
-
-
-
upper Paleozoic (4)
-
Wissahickon Formation (2)
-
-
palynomorphs
-
acritarchs (7)
-
-
paragenesis (5)
-
petroleum (5)
-
petrology (2)
-
Phanerozoic (4)
-
phase equilibria (2)
-
placers (1)
-
Plantae (2)
-
plate tectonics (71)
-
Precambrian
-
Archean
-
Neoarchean (1)
-
-
Baltimore Gneiss (1)
-
upper Precambrian
-
Proterozoic
-
Coldbrook Group (2)
-
Dedham Granodiorite (2)
-
Mesoproterozoic
-
Belt Supergroup (1)
-
Fordham Gneiss (1)
-
-
Neoproterozoic
-
Cryogenian (2)
-
Ediacaran (23)
-
Hadrynian
-
Fourchu Group (1)
-
-
Maranon Complex (1)
-
Moine Supergroup (1)
-
Tonian (6)
-
Vendian (4)
-
-
Paleoproterozoic (8)
-
-
-
-
problematic fossils (1)
-
sea-floor spreading (2)
-
sea-level changes (4)
-
sedimentary rocks
-
carbonate rocks
-
dolostone (1)
-
limestone (1)
-
-
chemically precipitated rocks
-
evaporites (1)
-
iron formations (1)
-
ironstone (1)
-
-
clastic rocks
-
arkose (1)
-
black shale (2)
-
conglomerate (4)
-
diamictite (2)
-
graywacke (3)
-
mudstone (8)
-
red beds (1)
-
sandstone (29)
-
shale (2)
-
siltstone (3)
-
-
coal (1)
-
-
sedimentary structures
-
biogenic structures
-
bioturbation (2)
-
stromatolites (1)
-
-
soft sediment deformation (1)
-
-
sedimentation (8)
-
sediments
-
clastic sediments
-
sand (1)
-
-
-
South America
-
Amazonian Craton (4)
-
Andes
-
Eastern Cordillera (1)
-
-
Peru (2)
-
-
stratigraphy (1)
-
structural analysis (9)
-
sulfur
-
S-34/S-32 (4)
-
-
tectonics (98)
-
United States
-
Alabama
-
Tallapoosa County Alabama (1)
-
-
Alaska
-
Alexander Archipelago (1)
-
-
Anadarko Basin (3)
-
Arizona
-
Mogollon Rim (1)
-
-
Arkansas
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Clark County Arkansas (1)
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Pike County Arkansas (1)
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Pulaski County Arkansas (1)
-
-
Arkoma Basin (2)
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Blue Ridge Mountains (1)
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Bronson Hill Anticlinorium (2)
-
California (1)
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Carolina Terrane (5)
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Colorado (1)
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Colorado Plateau (1)
-
Connecticut
-
New London County Connecticut (1)
-
Windham County Connecticut (1)
-
-
Connecticut Valley (1)
-
Delaware
-
New Castle County Delaware (1)
-
-
Delaware Basin (1)
-
Denver Basin (1)
-
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Ganderia
U-Pb zircon ages from metasedimentary and plutonic rocks in the Bras d’Or terrane of Cape Breton Island, Nova Scotia, Canada: insights into the Ediacaran–Cambrian tectonomagmatic evolution of Ganderia
ABSTRACT Avalonia and Ganderia are composite microcontinental fragments in the northern Appalachian orogen likely derived from Gondwanan sources. Avalonia includes numerous Neoproterozoic magmatic arc sequences that represent protracted and episodic subduction-related magmatism before deposition of an Ediacaran–Ordovician cover sequence of mainly siliciclastic rocks. We characterized the nature of the basement on which these arcs were constructed using zircon grains from arc-related magmatic rocks in Atlantic Canada that were analyzed for their Lu-Hf isotope composition. The majority of zircon grains from Avalonia are characterized by initial 176 Hf/ 177 Hf values that are more radiogenic than chondritic uniform reservoir, and calculated crust formation Hf T DM (i.e., depleted mantle) model ages range from 1.2 to 0.8 Ga. These data contrast with those from Ganderia, which show typically positive initial εHf values and Hf T DM model ages that imply magmatism was derived by melting of crustal sources with diverse ages ranging from ca. 1.8 to 1.0 Ga. The positive distribution of initial εHf values along with the pattern of Hf T DM model ages provide a clear record of two distinct subduction systems. Cryogenian–Ediacaran magmatism is interpreted to have resulted from reworking of an evolved Mesoproterozoic crustal component in a long-lived, subduction-dominated accretionary margin along the margin of northern Amazonia. A change in Hf isotope trajectory during the Ediacaran implies a greater contribution of isotopically evolved material consistent with an arc-arc–style collision of Ganderia with Avalonia. The shallow-sloping Hf isotopic pattern for Paleozoic Ganderian magmatism remains continuous for ~200 m.y., consistent with tectonic models of subduction in the Iapetus and Rheic Oceans and episodic accretion of juvenile crustal terranes to Laurentia.
Abstract The Neoproterozoic tectonomagmatic evolution of West Avalonia comprises four major events. Tectonism started with the formation of a Tonian passive margin on a Baltica-derived ribbon dispersed into the Mirovoi Ocean. Obduction of an oceanic terrane onto the ribbon produced olistostromes, deformation and metamorphism before 750 Ma. Obduction was followed by a Tonian (750–730 Ma) arc on the created composite crust. A pause in magmatism between 730 and 700 Ma is the next event. Subsequently, a Cyrogenian (700–670 Ma) arc was formed, which may have collided with Baltica or another buoyant element nearby. Thereafter, a long-lasting (640–565 Ma) continental arc was erected which, combined with the late Ediacaran–Early Paleozoic sedimentary cover, represents the hallmark of West Avalonia. A Caribbean-style incursion of the Ediacaran arc into the widening Tornquist gap between Amazonia and Baltica led to a diachronous collision with the Ganderian arc. Strike-slip slivering produced a complex transfer of terranes to both: Carolinia and smaller terranes to Ganderia, and East Avalonia to West Avalonia. The Rheic Ocean opened diachronously at c. 500 Ma, following a plate reorganization and re-establishment of an oblique subduction zone beneath Amazonia. As a result, Avalonia and Ganderia became progressively separated and dispersed into the Iapetus Ocean.
Peri-Gondwanan Ordovician arc magmatism in southeastern Ireland and the Isle of Man: Constraints on the timing of Caledonian deformation in Ganderia
New age data refine extent and duration of Paleozoic and Neoproterozoic plutonism at Ganderia–Avalonia boundary, Newfoundland
Ganderia–Laurentia collision in the Caledonides of Great Britain and Ireland
Provenance and tectonic evolution of Ganderia: Constraints on the evolution of the Iapetus and Rheic oceans
Middle Cambrian to Ordovician arc-backarc development on the leading edge of Ganderia, Newfoundland Appalachians
The evolution of many modern intra-oceanic and continental arc systems is exemplified by cycles of arc construction, rifting, and separation of remnant and active arcs by a backarc basin floored by oceanic crust. Rifted arc complexes and backarc basins are inherently subductable, and hence only a fragmentary record of rifting and arc construction is preserved in the ancient record. In this contribution, we synthesize available geochronological, geochemical, isotopic, and stratigraphic data in order to discuss the evolution of the Cambrian to Ordovician Penobscot-Victoria Arc, which developed on the leading edge of Ganderia, a peri-Gondwanan microcontinent. Although the Penobscot and Victoria stages of arc-backarc development occurred in a predominantly extensional suprasubduction-zone setting, they each display a distinctly different character of magmatism and sedimentation. These stages are separated by an orogenic episode marked by the obduction of backarc ophiolites onto the Ganderian passive margin. The Cambrian to Lower Ordovician Penobscot Arc is characterized by the continuous migration of the magmatic front and development of multiple volcanically active rift zones. The rift basins display a variety of characteristics, including bimodal calc-alkaline magmatism, felsic-dominated incipient rift magmatism, and formation of rifts floored by tholeiitic to boninitic suprasubduction-zone ophiolite. Comparison to modern analogues suggests that part of the Penobscot Arc area developed in a similar setting to the volcanically active Havre Trough and Taupo volcanic zone. In contrast, the Victoria Arc phase was dominated by multiple epiclastic rich, volcano-sedimentary basins overlying tectonically modified Penobscot basement. Igneous rocks are sparse, typified by calc-alkaline felsic volcanic and tholeiitic to alkaline backarc basin basalts. The change in character of the backarc volcanic rocks over time is interpreted to reflect multiple tectonic factors, including the variation of slab retreat rate, degree of extension in the arc (Cambrian Penobscot Arc) versus the backarc basin (Ordovician Exploits-Tetagouche backarc), reactivation of inverted Penobscot extensional faults during Middle Ordovician rifting, and/or depletion of fertile components by the Middle Ordovician.